BRPI0613385A2 - aluminum alloy blade - Google Patents

Abstract

An aluminium alloy product having a gauge below 200 μm and a composition, in weight %, of Fe 1.0-1.8, Si 0.3-0.8, Mn up to 0.25, other elements less than or equal to 0.05 each and less than or equal to 0.15 in total, balance aluminium. A process of manufacturing the product includes the steps of continuous casting an aluminium alloy melt of the above composition, cold rolling the cast product without an interanneal step to a gauge below 200 μm and final annealing the cold rolled product. The product may be a deep drawn container.

Description

Patent Descriptive Report for "ALUMINUM DELIGA BLADE".

The present invention relates to a method for producing an aluminum alloy product having a thickness below 200 μιη. It also refers to an aluminum alloy product having a thickness below the same value and to a-packers for application of packaging made from such an aluminum alloy product.

Aluminum alloys have been used for many years as a blade for household cooking, food packaging and other applications. A number of alloy compositions have been developed for uses and they include alloys based on compositions AA8006, AA8011, AA8111, AA8014, AA8015, AA8021 and AA8079 (where these compositions are those designated by the International Association of America recognized standards). 3XXX series alloys can also be used for blade applications, for example AA3005 alloy. AA8079 or AA8021 alloys have a high Fe content and a low Si content. AA8011 type alloys have a more balanced Fe and Si content and such decomposition variations affect the type of intermetallic phases formed during solidification, which in turn affect the final stiffening response.

In a continuous bending process alloys containing a higher Si content are considered to reduce banding productivity because the segregation axis effect becomes worse at higher casting speeds.

When producing thin sheet products it is generally considered that the laminate product cannot become very hard otherwise it will become difficult to laminate the blade to its final thickness. For this reason, blade producers typically incorporate an inter-stiffening step to soften the cold rolled product prior to final cold rolling.

A product that is only cold rolled will have high strength (due to hardening work) but limited ductility. To increase ductility and thereby make products suitable for handling and forming, a final stiffening operation is performed, either through batch stiffening or a continuous stiffening line. The essential variables are temperature and time and, depending largely on From these factors, recovery, recrystallization and grain growth processes can progress within the cold worked product. In products as thin as blades, the parameters are adjusted to ensure that a small grain structure is maintained, the large grains having a detrimental impact on mechanical properties.

The microstructure of a cold-rolled steel plate or sheet consists of fine grains of a micron scale and a high density of intermetallic phases formed during solidification. The intermetallic phases are broken during rolling and have a typical particle size between 0.1 and 1.5 μιη. This provides the main prerequisite for a great stiffening response. The other important metallurgical feature is the high degree of cold rolling resulting in a fine grain structure. However, these grain structures are highly anisotropic. During recovery the number of displacements is reduced and may form a sub-frame structure. As time or temperature increases, the size of the subgrowth increases gradually. Initially, in such a case, there is no appreciable change for the microstructure, with the product retaining much of its anisotropy. Although there is a significant drop in cold rolling state strength and an increase in ductility, ductility may not reach the levels achieved in a partially recrystallized material.

As temperature or time increases, recrystallization begins, with the gradual formation of a new, noticeable grain structure. Delaying forces, in the form of precipitation at the grain boundaries / intermetallic phases, trap the grain edges during recrystallization to restrict grain growth. Tightening treatment can, if there is sufficient supersaturated solute within the alloy matrix, also lead to the formation of fine intermetallic dispersoids. These also help to prevent grain growth. For some alloys (high Fe / low Si variety, for example), optimal properties can be achieved only through a narrow stiffening aperture. , usually at high stiffening temperatures. These higher temperatures are necessary because the high submicron particle density means that the gripping effect of the grains is already high. In addition, during stiffening, precipitation of intermetallic dispersoids reinforces the effect of grain edge trapping.

In fact, there is no continuous recrystallization reaction in a low temperature range and should only start at about 380 ° C and above. Only when the dispersoids / intermetals become grosser at higher temperatures do the forces holding the edges begin to decline and grain reorganization is possible. However, since the temperatures at this point are very high, the metal then enters a regime where the balance between the forces driving grain growth and gripping of the grain edges is unstable and uncontrolled grain growth can suddenly appear.

Production routes where direct cooling (DC) looping is used are more complicated and costly than continuous looping because they usually involve more processing steps, some of which are long and energy intensive, such as homogenization. It is therefore desirable to initially use continuous biasing to remove the homogenization steps and there has been substantial work in optimizing alloys and processes with this in mind. Even with a continuous slinging product to begin with, the reduction to final thickness usually involves a stiffening step, which is itself a costly and time consuming energy.

For most applications, and in particular for deep drawing applications, the ultimate strength of the alloy is not in itself the primary property. It is generally the case that as the strength of an alloy product increases, the elongation will decrease. In fact, the design of the alloy product is always to optimize the balance of its properties. A good balance in the case of deep stamping containers would be an optimal combination of strength and conformability (reflected by elastic stretching). This equilibrium can be assessed by multiplying the ultimate tensile strength (UTS) limit by the fault extension (E). In addition, it is desirable for the alloy to have a good balance of properties in both transverse and longitudinal directions, because conformation rarely occurs in one direction, if at all.

For some containers it is necessary that their walls have a certain degree of stiffness. The stiffness of a material is closely related to its yield limit (YS). Therefore, a good flow limit is also desirable. On the other hand, if YS is too close to UTS, an alloy product is not ideal for use in stamped containers. It is desirable for the alloy product to demonstrate hardening during deformation as this helps to avoid strangulation during forming. A product that connects with a YS near its' UTS has different deformation characteristics with limited hardening, if any.

With respect to deep stamping containers it is desirable that surface blackening should be avoided during forming operations which have been found to be related to the composition of the intermetallic phases after solidification.

In addition to these qualities, it is desirable, as a means of reducing alloy costs through recycling, to be able to accommodate elements such as Mn within the melt composition. In addition, it is desirable from an operational perspective to be able to process an alloy product through different production operations to enable better use of a range of available equipment such as batch stiffening and continuous stiffening furnaces.

WO 03/069003 describes a high Fe / low Si type alloy produced by a continuous lathing route. The alloy described comprises, in% by weight, Fe 1,5-1,9, Si <0,4, Mn 0,04 - 0,15, other elements and the aluminum balance. The processing route used to make this product is to continuously alloy the cold rolling with an optional inter-hardening with a final hardening after cold rolling between 200 and 430 ° C for a period of at least 30 hours. The preferred batch stiffening process is a two-step process involving a first step of between 200 and 300 ° C and a second step of between 300 and 430 ° C.

JP-A-03153835 describes a fin material for use in heat exchangers where the alloy composition is by weight% Fe 1.1 -1.5, Si 0.35-0.8, Mn 0.1 -0.4, the balance being aluminum. The alloy was sequentially insulated in water-cooled molds of 30 χ150 mm internal size, that is, on a laboratory scale. The Yingotate was hot rolled, intermediate rolled, cold rolled with a maximum cold rolling reduction of 30% to a thickness of 70 μηι. The description of intermediate iami-nation followed by a lower percentage of cold reduction suggests that an intermediate stiffness was used. The ultimate tensile strength limits between 13.0 and 14.7 kg / mm2 are reported (127 - 144MPa), presumably in the longitudinal direction, but no information is provided on YS, elongation, or transverse properties.

JP-A-60200943 discloses a similar alloy having a composition by weight of Fe 1.25-1.75, Si 0.41-0.8, Mn 0.10-0.70, balancing aluminum and impurities. This alloy has also been developed for use as fin material within welded heat exchangers. The alloy was dropped as an ingot, that is, semicontinuously DC, homogenized at 580 ° C for 10 hours and scalped. The ingots were then hot rolled at 525 ° C to a thickness of 4 mm and intermediate hardened at 380 ° C for 1 hour. They were then cold rolled to a thickness of 0.35 mm, with intermediate stiffening for the second time in a continuous process at a temperature of 480 ° C for 15 seconds and then cold rolled to a final thickness of 0.20. mm (ie 200 μιτι), and annealed at 205 ° C for 10 minutes to simulate a paint-aging treatment. A specific alloy has a YS of 13.7 kg / mm2, (134MPa), a UTS of 16 kg / mm2, (157 MPa), but the elongation is reduced to 9%, giving a product of UTS χ elongation of 1413. The same alloy is also shown with a YS of 4.916 kg / mm2 (48 MPa), a UTS of 12.0 kg / mm2 (118 MPa), and an elongation of 34%, giving a value of UTS χ elongation of 4012. There is no description of the transverse mechanical properties. However, the 10-minute treatment at 205 ° C is a recovery stiffening. Such stiffening will retain the anisotropy of the cold working process.

WO 02/064848 describes a process for producing a blade product wherein the alloy composition is by weight% Fe 1,2-1,7, Si0,4-0,8, Mn 0,07-0,20 , the remainder being aluminum and the incidental impurities. The alloy is cast continuously using a melt-belt, cold-rolled with a hardening at a temperature between 280-350 ° C, and subjected to final hardening. The final thickness is 0.3 mm (300 μm), and the final stiffening was a partial stiffening by a batch stiffening process involving heating the cold rolled product to between 250 and 300 ° C. After this processing route the alloy of this description developed a UTS around 125-160 MPa and elongation values between about 28 to 14.5%. Multiples of UTS and elongation can be calculated and they range from 2295 to 3476. No data are shown for transverse properties or for YS.

Other alloys are known and sold for food packaging applications. This includes AA8011 based alloys. AA8011 has a composition as follows, by weight%: Fe 0.6-1.0, Si 0.50-0.90, Cu <0.10, Mn <0.20, Mg <0.05, Cr <0.05. 0.05, Zn <0.10, Ti <0.08, other elements <0.05 and others totaling <0.15, the balance being Al. An alloy with Fe at the lower end of this range is known. , nominally Fe 0.65 and Si 0.65. This alloy is known with and without Mn and is known as continually sendting and is used for non-demanding products such as blades for household appliances. Another alloy is known with a nominal Fe content of 1.1 and Si also of 1.1. In these alloys, where the Fe to Si ratio is 1: 1, the addition of Mn leads to an unstable stiffening response at temperatures of 320 ° C and above. As a result, Mn is avoided in such alloys.

It is an object of this invention to provide a new and economical method of producing an aluminum alloy product, a method that brings a combination of good mechanical properties in terms of balance between strength and elongation in both longitudinal and transverse directions, which avoids Creation of blackening deposits during deep stamping operations and providing large processing windows for either a batch annealed or continuously annealed product.

It is another object of this invention to provide aluminum alloy products revealing an increased combination of properties particularly useful in the production of deep embossing containers which are therefore easy to conform and which do not tend to surface blackening defects.

Accordingly, a first aspect of the invention is a process for producing an aluminum alloy product comprising the following steps:

(a) continuously cast an aluminum alloy melt of the following composition (by weight%):

Fe: 1.0-1.8Si: 0.3-0.8Mn: up to 0.25

other elements less than or equal to 0.05 each and less than or equal to 0.15 in total

balance: aluminum

(b) cold rolling the Iingotized product without an intermediate hardening step to a thickness below 200 μιτι

(c) final hardening of cold rolled product

The alloy composition is chosen to create the proper balance of intermetals after solidification, control their size distribution (and thus the effect on the stiffening reaction), which determine the final microstructure and therefore , the balance of properties. By combining the alloy composition with this process route, a microstructure is developed that has a good balance between the driving forces of grain boundary mobility and the retarding forces required to stabilize grain size. This balance is stable over a wider range of coating conditions leading to greater flexibility in production operations. This is because the supersaturated Fe eMn solute (which leads to the formation of dispersoids during stiffening) and the intermetallic particles of the Iingotate structure both act as retarding forces against grain stiffening. In addition to this, it is possible to achieve high isotropic YS, UTS and elongation values and reduce surface blackening during forming operations.

The alloy composition is described in particular with respect to other elements and the aluminum balance, as recognized by the Aluminum Association Register of International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Alu-minum Alloys .

Fe is added to provide mechanical strength although, because the structure is dependent on the type of intermetallic and disperoid formed, its content should preferably be considered together with the Mn and Si content. If the Fe content is very low , the resulting mechanical resistance will be very low. If the Fe content is too high, it will promote the appearance of crude intermetallic phases and these phases may be detrimental to the surface quality of the stamped containers. Preferred embodiments are those wherein the amount of Fe present is between 1.1 and 1.7 wt%, and more preferably between 1.2 and 1.6 wt%.

The presence of Si helps reduce the solid Fe and Mn solution, allowing continuous recrystallization to begin within a low stiffening temperature range. The addition of Si in combination with Feajuda promotes the formation of cubic Si-AI (FeMn) Si phase and it has been found that a predominance of this phase rather than Si-free AI (FeMn) or AIFeSi monoclinic β-form helps to prevent formation. stains and blackening during deep stamping. It is a preferred feature of the invention that the predominant intermetallic phase present is cubic α-AI (FeMn) Si. If the Si content is too low, the precipitates will be binary AIFe. If Si content comes close to parity with Fe content according to the balanced AA8011 type alloys mentioned above, the α-phase is less likely to form and instead the AIFeSi β form will be formed.

The cubic phase is believed to have better adhesion to the matrix than the monoclinic β form or AIM phases (FeMn), (M = 4-6), and is less likely to peel off during conformation. As a result, the cubic α phase is less likely to stick to the mold surface and cause damage to the aluminum surface. An alternative hypothesis is that the shape of the cubic α phase during and after cold work has an effect. Because it is rounder than the monoclinic angular β form, fewer aluminum fines are generated during rolling and other forming operations. Fewer fines result in reduced damage and reduced surface damage. To promote the formation of α cubic phase, therefore, Si is present within a range of 0.3 to 0.8 wt%, preferably within the range of 0.4 to 0.7 wt%, and more preferably of 0 0.5 to 0.7% by weight. The Fe: Si ratio is preferably between 1.5 and 5, more preferably between 1.5 and 3.

Mn also promotes the formation of the cubic α-AIFeSi phase. Emadition, Mn provides a small booster effect. If the Mn content is too high, segregation problems will be encountered within the Iingote product continuously and the Iingote product will have to be homogenized. For this reason, if present, Mn is present in an amount of up to 0.25%. Since it is desirable to be able to use recyclable scrap and gain the benefit of promoting proper phase formation, it is preferred that Mn be present in an amount above 0.05% by weight. It is also preferred that Mn be present in an amount of 0.05 to 0.20%.

Although continuous sling can be performed in a variety of ways, including the single belt process, one preferred method is to employ double-roll sling. A preferred thickness of the Iingotized product is between 2 and 10 mm, more preferably between 3 and 8 mm. With respect to step (b), preferred configurations are those where the final gauge after cold rolling is below 180 μm, more preferably below 165 μm. It is preferred that the thickness is above 35 μm, more preferably above 60 μm, more particularly where the intended application is in food packaging containers.

Referring to step (c), the final stiffening can be performed by a batch stiffening process or by a continuous stiffening process. The final stiffening process establishes the ultimate balance of mechanical properties for the aluminum strip product. As explained above, it is important during this step to be able to control the recovery / recrystallization reaction that occurs with cold worked metal. Indeed, with this alloy and the process of the invention, a wide range of stiffening conditions can be used and good mechanical properties achieved.

If a batch stiffening process is used, the stiffening temperature is between 300 and 420 ° C. The product according to the invention is so stable during stiffening that the duration can be long, with times of up to 60 hours and more being possible, this duration even from slow heating to temperature and maintenance at this temperature. However, since excellent property matching can be achieved at shorter stiffening durations and due to a desire to minimize energy costs, it is preferable that the batch stiffening duration is between 10 and 45 hours.

Where continuous stiffening is used the temperature stiffening treatment is between 400 and 520 ° C, preferably between 450 and 520 ° C. The duration of the strip spent within the furnace is much shorter, usually on the order of seconds, for example between 4 and 10 seconds, and is generally adjusted to produce the necessary microstructural transformation during the stiffening step. Continuous stiffening in an industrial line can be simulated by immersing samples in furnaces adjusted to lower temperatures but for longer durations. The skilled person will understand that there is a range of factors to consider in controlling the continuous stiffening operation. For example, you can vary the velocity of the metal through the furnace depending on the thickness of the strip, the heat transfer conditions within the furnace (which may vary from furnace to furnace depending on the movement of air inside the furnace) and the maximum setting. of oven temperatures. Establishing optimal conditions for each continuous stiffening line is a established practice in the industry. With this invention it is possible to operate the continuous stiffening line with a wide range of adjustments and achieve the same results.

Following this process route an improved alloy product can be obtained compared to the prior art alloy products mentioned above.

A second aspect of the invention is an aluminum alloy product having a thickness below 200 μιη and comprising the following alloy composition by weight%:

Fe 1.0-1.8Si 0.3-0.8Mn to 0.25

other elements less than or equal to 0,05 each and less than or equal to 0,15 in total

the balance being aluminum

where the aluminum alloy product has the following properties:

in the transverse direction:

flow limit> 100 MPa

UTS> 130 MPa

elongation> 19%, and

UTS product χ stretching> 2500

and in the longitudinal direction:

flow limit> 100 MPa

UTS> 140 Lengthening> 18%, and

UTS product χ stretching> 2500

The alloy product of the second aspect of the invention may be obtained by the process of the first aspect of the invention.

The same issues with respect to the intermediate phases and their influence on the product stiffening reaction may be maintained and therefore the composition may be more preferably controlled in the same manner as described above.

With respect to mechanical properties it is preferable that the limited flow is> 110 MPa1 more preferably> 120 MPa1 and it is preferable that the longitudinal flow limit is> 110 MPa1 more preferably> 120 MPa.

It is preferable that the transverse UTS is greater than 135 MPa1, more preferably> 140 MPa. It is preferable that the longitudinal UTS is greater than 150 MPa.

The transverse elongation for the alloy product of the invention is preferably greater than 20% and more preferably 22%. The longitudinal length is preferably greater than 19% and more preferably greater than 20%.

For the product of the final limit of the tensile strength by elongation, for the transverse direction it is preferable to be> 3000 and for longitudinal direction it is preferable to be> 3000.

The process and the product according to the invention have a very useful balance of properties and adaptability so that their use can be contemplated within a wide range of blade applications including, but not limited to, deep embossing containers, smooth or lightweight counterparts. wrinkled walls and blades of cooking appliances.

The invention will now be illustrated with reference to the following examples, tables and figures. Examples 1 to 3 refer to final stiffening lotene and Examples 4 and 5 to continuous stiffening to final stiffening. All mechanical tests were performed according to DIN-EN 10002. YS and UTS values are always presented in MPa and elongation (E) as a percentage. "T" refers to the transverse direction and "L" to the longitudinal direction. All alloy contents are expressed in% by weight.

Example 1

Table 1 summarizes the investigated alloy compositions. Alloys 1 and 2 are alloys within the scope of the invention. Alloy 4 is an AA80T1 alloy with Fe in the direction of the lower end of the composition range, that is, similar to commercially available products but with addition of Mn. Alloy 5 is a prior art alloy WO 03/069003. For each composition the other elements were <0.05 each and <0.15 nototal with the Al balance.

All alloys were continuously bung in a double-roll bung up to the thicknesses shown in Table 1. They were then cold-rolled on a laboratory scale cold rolling mill to a final thickness of 150 μηι without a stiffening step. Each product of cold rolled alloys 1,4 and 5 was then subjected to batch hardening treatments at 320, 350, 380 and 410 ° C for periods of 20, 40 and 60 hours. Alloy 2 was batch annealed at these temperatures for a duration of 45 hours. Alloy 5 in particular has been found to have very inconsistent mechanical properties due to a completely different stress deformation behavior. As mentioned above, to assess the balance of strength and ductility, the product of UTS and elongation was calculated. Mechanical properties are shown in Tables 2, 3 and 4 and Figures 1 to 6.

<table> table see original document page 14 </column> </row> <table> Table 2: Test

and traction after batch hardening for 20 hours

<table> table see original document page 15 </column> </row> <table>

Table 3: Tensile data after 40 hours batch hardening (45 hours for alloy 2)

<table> table see original document page 15 </column> </row> <table> Table 4: Traction data after 60 hours batch stiffening

<table> table see original document page 16 </column> </row> <table>

As can be seen from Figures 1, 3 and 5, the alloy of the invention always has the best combination of UTS and elongation in the transverse direction compared to alloys 4 or 5. In the longitudinal direction (as shown by Figures 2, 4 and 6), alloy 5 is able to equalize the combination of UTS and elongation only when it is annealed at high temperatures. As described above, at such temperatures there is an increased danger of uncontrollable recrystallization and raw grain growth and this is unsatisfactory from a perspective. industrial processing. Alloy 2, also according to the invention, provides the best combination of properties, a combination that alloy 5 did not match. These results show that the process according to the invention provides a superior product and allows producers to choose a wider range of stiffening conditions.

Example 2

Alloy 1 was continuously bung in a double cylinder bung up to the same thickness as in Table 1 and then cold rolled into a laboratory scale cold bummer to a thickness of 1.5mm. At this point, some samples were subjected to a stiffening and others were not. For those inter-annealed, the heating rate was 50 ° C per hour and they were kept at a temperature of 320 ° C for 4 hours. They were then air-cooled. All samples were then cold rolled to a final thickness of 210 μm. Samples of the cold rolled product, with and without inter-stiffness, were subjected to four final batch stiffening treatments. All tensions lasted 4 hours and at temperatures of 250, 300 and 350 ° C.

The processing route with inter-hardening at 320 ° C and final hardening at 300 ° C reflects the production route recommended by WO02 / 064848. The mechanical properties of alloy 1 following these treatments are given in Table 5 and Figures 8 to 13. They show that there is a significant difference between the mechanical properties achievable with the present invention and the product produced according to WO 02/064848.

Table 5:

<table> table see original document page 17 </column> </row> <table>

The mechanical properties of alloy 1 after processing according to WO 02/064848 are always inferior to those of the new inventive method in both transverse and longitudinal directions. In particular, the OYS for inter-annealed samples was considerably lower when the final stiffening was at 300 ° C and above.

To investigate the effect of inter-stiffening on properties after continuous stiffening, alloy 1 samples processed in the same manner as described in the above Example to a thickness of 210 μιτι, without inter-stiffening, were immersed in an oven at 350 ° C for 10 hours. minutes to simulate continuous stiffening. The transverse properties are shown in Table 6.

Table 6:

<table> table see original document page 18 </column> </row> <table>

As with batch stiffening, the YS of the inter-annealed version was much lower than the method of the invention.

Example 3

To demonstrate the typical level of properties that can be achieved on an industrial scale and in different thicknesses, alloy 2 is continuously cast by double-barreled lathing up to. same thickness of Example 1 and cold rolled in an industrial cold laminator to 78 and 116 μιτι thicknesses without inter-stiffness using conventional cold rolling pass programming. The 78 μιτι cold rolled product was batch annealed at 350 ° C for 25 hours and the 116 μιη product was annealed at 320 ° C for 30 hours. The results of the mechanical tests are shown in Table 7.Table 7:

<table> table see original document page 19 </column> </row> <table>

While Examples 1 and 2 illustrate the relative advantages of the process of the invention as applied to alloys 1 and 2 over the prior art, this Example illustrates the type of properties achievable in complete industrial production.

Laboratory-scale cold rolling, as used in Examples 1 and 2, involves different thermal and pressure conditions.

In an industrial laminator the strip is deformed / reduced in thickness to a greater extent with each pass. As a result, your temperature rises in the direction of 100 ° C or more. After a pass the hot strip is cooled and the thermal mass means that the coil retains heat for some time. As the temperature increases the recovery may begin so that the recovery is occurring both during subsequent rolling and when the metal is coiled. The recovery that occurs in this way is known as dynamic recovery, and since recovery increases ductility, it explains the increased properties seen after processing on an industrial scale, especially in relation to stretching.

Example 4

Alloys 1, 4 and 5 were lynched and rolled to a final gauge in the same manner as described in Example 1. They were then immersed in a hot oven for 10 minutes at each temperature of 320, 350,380 and 410 ° C to simulate a continuous stiffening line on an industrial scale. Mechanical properties only in the transverse direction are shown in Table 8 and Figure 7. Only the transverse properties are shown because it is the transverse properties that generally represent the worst scenario for ductility. Good ductility in transverse direction generally corresponds to good ductility in longitudinal direction.

Table 8:

<table> table see original document page 20 </column> </row> <table>

As shown by these results, the alloy of the invention always had better balance of mechanical properties. Although the elongation values measured here for the process of the invention are relatively low, it should be remembered that such tests were conducted on the laminate using a laboratory scale laminator. Therefore, they have not experimented with the kind of dynamic recovery process required to provide optimal properties. But these results show a relative combination of properties for different alloys. In fact, this data illustrates that alloy 5 cannot be annealed continuously, making it an alloy product less adaptable for industrial processing in different production plants.

Alloy 1 was double-barreled to a thickness of 6.05 mm and then cold-rolled on an industrial non-stiffening cold rolling mill to final thicknesses of 79 μm and 120 μm using the pass settings. conventional. Coils of both thicknesses were then annealed continuously by passing them through an oven set at a temperature of 499 ° C. For the 120 μm thickness plate, the strip velocity was 125 m / min and the duration inside the oven was about 6 seconds. For the 79 μm thick blade the speed of the strip was 160 m / min giving a duration within the oven of around 6 seconds. The mechanical properties are shown in Table 9.

Table 9:

<table> table see original document page 21 </column> </row> <table>

The product at a thickness of 120 μm was then successfully formed into deep drawing vessels with walls lysing any sign of surface blackening. Similarly, the product with a thickness of 79 μm was formed into containers with wrinkled walls with no sign of surface blackening.

An alloy of the following composition: Fe 1.50, Si 0.60, and Mn 0.09, other elements <0.05 each and <0.15 in total, the balance being Al, was double-cylinder Iingota-da up to a thickness of 6.29 mm and then cold rolled in an industrial laminator to a thickness of 135 μm using conventional pass schedules. It was then subjected to 10-minute simulated continuous stiffening treatments in an oven at 325, 350 and 375 ° C. The mechanical properties are shown in Table 10. Table 10:

<table> table see original document page 22 </column> </row> <table>

The results of this example show that it is possible, with an alloy made according to the invention and on an industrial scale continuous stiffening line, to achieve a very good combination of both longitudinal and transverse directions. The results also show that it is possible, with the alloy and the process according to the invention, to obtain similar properties over a wide range of thicknesses and strip speeds. A consistent stiffening response such as this is very useful for flexible production.

In addition, the consistency of the results when compared to the industrial scale batch stiffening result of Example 3 shows that the alloy and process of the invention allow for highly flexible production in the sense that a producer is not limited to a single adjustment. heat treatment equipment available, but can switch from batch stiffening to continuous stiffening and still expect similar product characteristics.

Claims (22)

1. Production process of an aluminum alloy product comprising the following steps: (a) Continuous sealing of an aluminum alloy melt of the following composition (by weight%): Fe 1.0-1.8Si 0.3-0 1.8Mn to 0.25other elements less than or equal to 0.05 each and less than equal to 0.15 in total The balance being aluminum (b) cold rolling of the Iingotated product without a de-stiffening step to a thickness below 200 μιτι (c) final hardening of cold-rolled product A process according to claim 1, wherein the continuous biasing (a) takes place on a double-cylinder biasing. The process according to claim 1 or 2, wherein the Fe βor is from 1.1 to 1.7% by weight. A process according to claim 3, wherein the Fe content is 1.2 to 1.6% by weight. Process according to any one of claims 1 to 4, wherein the Si content is 0.4 to 0.7% by weight. The process according to claim 5, wherein the Si content is 0.5 to 0.7% by weight. A process according to any one of claims 1 to 6, wherein the Fe: Si ratio is between 1.5 and 5. A process according to claim 7, wherein the Fe: Si ratio is between 1.5 and 3. A process according to any one of claims 1 to 8, wherein the predominant intermetallic phase is the cubic α-AIFeSi phase. A process according to any one of claims 1 to 9, wherein the Mn ower is 0.05 to 0.25 wt%. A process according to claim 10, wherein the Mn content is 0.05 to 0.20% by weight. The process of claim 11, wherein the Mn content is from 0.05 to 0.15% by weight. A process according to any one of claims 1 to 12, wherein the final stiffening (c) is a batch stiffening. The process according to claim 13, wherein the batch stiffening is performed in the temperature range of 300 to 420 ° C. The process according to claim 14, wherein the batch stiffening is performed in the temperature range 300 to 380 ° C. The process according to claim 15, wherein the batch stiffening is performed in the temperature range 320 to 380 ° C. A process according to any one of claims 1 to 12, wherein the final stiffening (c) is a continuous stiffening. The process according to claim 17, wherein continuous stiffening is performed in the temperature range of 400 to 520 ° C. The process according to claim 18, wherein continuous stiffening is performed in the temperature range 450 to 520 ° C. 20. Aluminum alloy product having a thickness below 200um and the following composition by weight: Fe 1.0-1.8Si 0.3-0.8Mn to 0.25other elements less than or equal to 0.05 each and less than or equal to 0.15 in the total balance being aluminum where the aluminum alloy product has the following properties: in transverse direction: yield limit> 100 MPaUTS> 130 MPa lengthening> 19, and UTS product χ lengthening> 2500 in the direction longitudinal: yield limit> 100 MPaUTS> 140 MPa elongation> 18, and UTS product χ elongation> 2500. The product of claim 20, which may be obtained by the process as defined in any one of claims 1 to 19. Deep stamping container produced from the alloy product as defined in claim 20 or 21.